In the field of wireless communication, currently a plurality of systems exists, such as a global system for mobile communications (GSM), a code division multiple access (CDMA) system, a universal mobile telecommunication (UMTS) system, a long term evolution (LTE) system, and a worldwide interoperability for microwave access (WiMAX) system. With the development of the communication technology, demands for co-existence and smooth evolvement of a plurality of systems appear. In an existing multi-mode coexistent communication system, a plurality of systems is completely independent or one system thereof accomplishes convergence and combination functions.
In the prior art, a solution that a plurality of systems is completely independent is as shown in FIG. 1 (taking a system that CDMA and LTE are coexistent as an example), a base band unit (BBU) and a remote radio unit (RRU) of each system are completely independent. The multi-mode coexistence only includes a multi-mode common station address and practically base stations are completely independent. The solution has the following disadvantages. During multi-mode independent configuration, optical fiber transmission from a base station to a remote RRU can not be shared, and a remote radio frequency module can not be shared at the same frequency band.
In the prior art, a solution of transparent transmission through one system when a plurality of systems coexists is as shown in FIG. 2. In an example that CDMA and LTE coexist, quadrature base band service data (in-phase and quadrature-phase, IQ) of the CDMA and operation maintenance data of the CDMA RRU are firstly sent to a base band processing unit of the LTE (LTE BBU). The base band processing unit of the LTE is combined into the base band IQ data of the LTE and the operation maintenance data of the LTE RRU and sent to the RRUs of the LTE and CDMA through optical fibers or cables. The inventors find that the solution in the prior art has the disadvantages as follows after researching. The content of the plurality of systems is converged by using one system among the systems, so that the complexity of the convergence system is increased. The convergence manner and mode are closely coupled, so that flexibility of the multi-mode coexistence is decreased. The convergence manner and mode are closely coupled, which adversely affects smooth evolvement among the plurality of systems˜